Hello,I started to read in a book about the pineal gland, but I have some questions about it:1) Is it true that the melatonin decolorates the skin of the inferior vertebrates(amphibians and reptiles)?2) Do you know any other hormones produced by the pineal gland (except melatonin) and if it produces serotonin to inhibate the gonads ? 3) Is it true that the pineal gland has a hypoglycemiant role?

that's about as vague as you can put it. A statement like that has no real meaning.In the broadest sense, all endocrine glands influence all metabolisms, because they interact with one another. But directly, melatonin does not have any metabolic effects.

"As a biologist, I firmly believe that when you're dead, you're dead. Except for what you live behind in history. That's the only afterlife" - J. Craig Venter

I understand....and is it wrong if somewhere it says: "The extracts of the pineal gland have metabolic role, in the meabolism of proteins, minerals, glucose or lipids", (without saying if they have a direct influence or not)?